As is well known, there are many useful aromatic compounds containing side chains which bear at least one halo substituent having an atomic number below 20. Such compounds may be synthesized by various techniques, including some otherwise attractive techniques which have the disadvantage of resulting in the formation of aromatic materials that contain unwanted ar-iodo or ar-bromo substituents as well as the desired halo-substituted side chains. Regardless of whether these ar-halo substituents are present in the same compound as the halo-substituted side chains or in a compound that is in admixture with the desired product, it is difficult to remove them without also removing the halo substituents on the side chains.
March, Advanced Organic Chemistry, Second Edition, McGraw-Hill, New York, pp. 517-518, teaches the use of various metals and metal compounds in removing halogen from aromatic rings. Akagah et al., Chemical Abstracts, Vol. 103, 123081e, 1985, teach that haloarenes, such as chlorobenzene and p-fluorotoluene, can be reduced with a particular activated aluminum.